It was found that a decrease in α1PI blood levels is directly correlated to a decrease in CD4 lymphocytes (Bristow et al., 2001; Bristow et al., 2012): In a pilot study to determine whether α1PI therapy might benefit the CD4 counts in HIV-1 infected patients (Clinicaltrials.gov NCT01370018), HIV-1 patients with infection-related α1PI deficiency received weekly α1PI therapy (120mg/kg) for a period of 8 weeks and results were compared with those of patients having the inherited version of α1PI deficiency who were simultaneously receiving weekly α1PI therapy (60mg/kg). None of the patients in the study had ever previously received α1PI therapy. It was found that CD4 cells rose to normal levels following 2 weeks of intravenous α1PI therapy with no adverse effects observed in the HIV-1 patients (n=3) or the control group of HIV-1 uninfected, α1PI deficiency patients (n=2). The new crop of CD4 cells were functional, capable of fighting infection, and appeared to be generated from bone marrow-derived stem cells (Bristow et al., 2010). As a bonus, it was found in the HIV-1 patients that LDL levels (bad cholesterol) decreased and HDL levels (good cholesterol) increased {Bristow et al., in review).